P0325 Hyundai Tucson
Knock Sensor 1 Circuit Malfunction (Bank 1) · Powertrain Code · Medium
What is P0325?
The knock sensor 1 on bank 1 is not functioning properly. The ECM cannot detect engine knock/detonation.
When the Hyundai Tucson triggers code P0325 (knock sensor 1 circuit malfunction (bank 1)), it typically points to an issue in the powertrain system. Below you'll find the most common causes, symptoms, and repair options specific to the Hyundai Tucson.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Hyundai Tucson.
Common Causes on Hyundai Tucson
- Failed knock sensor (very common on Theta II engines)
- Knock sensor wiring harness damage from engine heat
- Engine knock from low-octane fuel or carbon buildup
- Theta II engine rod bearing wear causing real knock detected by sensor
- Corroded knock sensor connector
Symptoms
- Check Engine Light on
- Reduced engine power (ECM retards timing)
- Slightly worse fuel economy
- Engine may feel sluggish on acceleration
Notes for Hyundai Tucson
On Theta II engines, a knock sensor code can indicate the beginning of rod bearing failure; always investigate further.
